[ hek-sag-uh-nl ]
/ hɛkˈsæg ə nl /


of, relating to, or having the form of a hexagon.
having a hexagon as a base or cross section: a hexagonal prism.
divided into hexagons, as a surface.
Crystallography. noting or pertaining to a system of crystallization in which three equal axes intersect at angles of 60° on one plane, and the fourth axis, of a different length, intersects them perpendicularly.

Nearby words

  1. hexadecimal,
  2. hexaemeron,
  3. hexaethyl tetraphosphate,
  4. hexafluoride,
  5. hexagon,
  6. hexagonally,
  7. hexagram,
  8. hexahedron,
  9. hexahemeron,
  10. hexahydrate

Origin of hexagonal

First recorded in 1565–75; hexagon + -al1

Related formshex·ag·o·nal·ly, adverbpseu·do·hex·ag·o·nal, adjectivepseu·do·hex·ag·o·nal·ly, adverbsub·hex·ag·o·nal, adjective

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for pseudohexagonal


/ (hɛkˈsæɡənəl) /


having six sides and six angles
of or relating to a hexagon
crystallog relating or belonging to the crystal system characterized by three equal coplanar axes inclined at 60° to each other and a fourth longer or shorter axis at right angles to their planeSee also trigonal
Derived Formshexagonally, adverb

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for pseudohexagonal



1570s, from hexagon + -al (1). Related: Hexagonally.

Online Etymology Dictionary, © 2010 Douglas Harper

Science definitions for pseudohexagonal


[ hĕk-săgə-nəl ]

Having six sides.
Relating to a crystal having three axes of equal length intersecting at angles of 60° in one plane, and a fourth axis of a different length that is perpendicular to this plane. The mineral calcite has hexagonal crystals. See illustration at crystal.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.